Field of the Invention
The present invention relates to a loop antenna, and in particular to a loop antenna with a radiation field that is more symmetrical in different directions.
Description of the Related Art
Near-field communication antennas are commonly utilized in portable electronic devices or cards, which provide non-contacting data matching, data exchanging or payment. Restricted by the dimensions of the carriers (for example, cell phones or credit cards), near-field communication antennas are rectangular. Therefore, as shown in FIG. 1, in a field density test, the radiation energy of near-field communication antennas decays in directions of 90 degrees and 270 degrees.